Liquid controlled dashpot

ABSTRACT

A housing including opposite ends and a central partition. A pair of opposing resilient cups are disposed within the housing ends and have their open ends sealed relative to the marginal portions of the partition, the latter having a fluid passage therethrough controlled by a one-way valve defining a bleed passage there past when closed. One end of the housing includes a tubular neck having a piston rod slidingly disposed therein provided with a head on its inner end opposing the outer surface of the adjacent cup end wall and the cups and passage are filled with liquid.

if States Patent 2.919.883 1/1960 Murphy......................1. 188/87 X 3.081.846

[72] Inventor Benjamin C. Benjamin Flint, Mich. Appl. No. 834,051

FOREIGN PATENTS 4/1966 Great Britain.........1.

Primary ExaminerGeorge E. A. Halvosa [22] Filed June 17,1969 [45] Patented Nov. 16,1971

[73] Assignee Schmelzer Corporation Attorneys-Clarence A. OBrien and Harvey B. Jacobson [54] LIQUID CONTROLLED DASHPOT 8 Claims, 5 Drawing Figs.

ABSTRACT: A housing including opposite ends and a central partition. A pair of opposing resilient cu the housing ends and have their 0 the marginal portions of the partition. the latter havin passage therethrough controlled b bleed passage there past when clo [51] [50] FieldofSearch............... 88.1,94, 100 R, 298, 232; 267/23. 24. 34

includes a tubular neck having a piston rod slidingly disposed therein provided with a head on its inner end opposing the outer surface of the adjacent cup end wall and the cups and passage are filled with liquid,

8 T N m MA w mm .mA mm m N N U m H 1,995,721 3/1935 Sanford...........4.....

PATENTEDuuv 1819?! 3,620,523

sum 2 OF 2 Benjamin 6. Benjamin 'INVIiN'I m.

LIQUID CONTROLLED DASHPOT This invention relates to a novel fluid controlled throttle return check assembly and more specifically to an assembly to be used in conjunction with automotive internal combustion engine carburetors.

The dashpot of the instant invention is primarily designed for use in conjunction with conventional automotive carburetors and the like and is particularly well adapted to check the return of movable throttle controls of an associated carburetor to the idle position.

While the manufacturers of automotive carburetors have for some time been capable of producing a carburetor so compatible with the improved internal combustion engines presently utilized in automobiles that the throttle controls of the carburetors may be rapidly opened and almost immediately fully closed to the idle positions without the associated combustion engine stalling, more recent automotive engines have had numerous power draining accessories mounted thereon which increases the tendency of such engines to stall when the throttle controls thereof are rapidly moved to the full idle positions.

As a result of this increased tendency for the automotive engines to stall automotive engine designers provided their engines with dashpots specifically designed to allow rapid movement of the carburetor throttle controls toward almost full idle positions and to then retard final movement of the throttle control to its full idle position. While the dashpots presently utilized on automotive engines for this purpose at least generally achieve the desired results, many operate by controlling atmospheric air passage past a valving structure. These air controlled dashpots are capable of functioning almost completely as desired until the air valving components thereof have been contaminated with dirt and oil after continued use on an associated internal combustion engine. Further, many conventional dashpots are constructed and so mounted on an associated combustion engine as to require adjustment of the dashpot each time the carburetor throttle or idle controls are adjusted.

In addition, present governmental controls on exhaust and crankcase emissions from automobile engines operated in this country have necessitated that the automotive industry specifically design their engines for reduced exhaust and crankcase emissions. Some of the designs for reducing these emissions result in further tendency of the associated combustion engines to stall and accordingly, a need has developed for a more efficient, trouble-free and inexpensive dashpot for controlling the return of carburetor throttle linkage toward the full idle positions. Still further, in view of the critical tuning procedures which must be followed in tuning a present-day automotive engine so as to maintain its exhaust and crankcase emissions as low as possible, a further need has developed for a dashpot that does not need to be independently adjusted each and every time associated throttle linkage and idle controls need to be adjusted.

Accordingly, his the main object of this invention to provide a carburetor throttle controlling dashpot which will be capable of accurately and effectively retarding the return of throttle linkage to the full idle position in only the last portion of movement of that throttle linkage to the idle position.

Another important object of this invention is to provide a dashpot controlled by liquid as opposed to air thereby enabling the utilization of larger valving passages less subject to clogging so as to provide a more reliable dashpot and one which will operate under extreme temperature conditions.

Still another important object of this invention is to provide a dashpot controlled by liquid and which will therefore be fully sealed, as to its liquid movement controlling components, from the ambient atmosphere and contamination therefrom.

Another very important object of this invention is to provide a dashpot including structural components enabling it to be utilized on substantially all automotive carburetors with only minor modifications to those carburetors being required.

A further important object of this invention is to provide a dashpot constructed in a manner whereby it may serve the dual functions of a throttle return check and an idle adjustment.

A final object of this invention to be specifically enumerated herein is to provide a dashpot in accordance with the preceding objects which will conform to conventional forms of manufacture, be of simple construction and easy to install so as to provide a device that will be economically feasible, long lasting and readily adaptable to substantially all types of throttle linkage.

These together with other objects and advantages which will become subsequently apparent reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming a part hereof, wherein like numerals refer to like parts throughout, and in which:

FIG. l is a side elevational view of a conventional form of carburetor with the dashpot of the instant invention operatively associated with a throttle linkage portion of the carburetor;

FIG. 2 is an enlarged fragmentary horizontal sectional view taken substantially upon the plane indicated by the section line 2-2 of FIG. 1 and with portions of the carburetor body from which the dashpot is supported being broken away and illustrated in horizontal section;

FIG. 3 is a vertical transverse sectional view taken substantially upon the plane indicated by the section line 3-3 of F IG. 2.

FIG. 4 is an enlarged longitudinal sectional view of the dashpot; and

FIG. 5 is an exploded perspective view of the internal portions of the dashpot enclosed within the housing thereof and with fragmentary portions broken away and illustrated in section.

Referring now more specifically to the drawings, the numeral 10 generally designates the intake manifold of a conventional form of combustion engine. A carburetor referred to in general by the reference number 12 and of conventional design is mounted on the intake manifold in any convenient manner (not shown) and the carburetor 12 includes a body 14 and at least one throttle plate shaft 16 which is journaled transversely through the carburetor 12. The throttle shaft 16 is operatively associated with throttle linkage 18 for oscillating the throttle shaft 16 between its open and closed positions and the throttle linkage 18 includes a portion 20 which is movable in a generally horizontal direction as the throttle linkage l8 approaches its fully closed position. The throttle linkage 18 includes a fast idle cam 22 and an adjustable abutment 24 operatively associated with the fast idle cam and the latter is actuated by a connecting line 26 extending from the fast idle cam 22 to a crank arm portion 28 mounted upon a choke plate shaft 30 also journaled transversely through the carburetor l2 and having a choke plate (not shown) mounted thereon interiorly of the body 14.

It is of course to be understood that the choke plate shaft 30 may be automatically controlled by means of a conventional bimetallic control sensitive to engine heat.

The body 14 includes an outwardly projecting mounting boss 32 having a threaded bore 34 formed therethrough. The mounting boss 32, if not already present on an existing carburetor, need be the only modification of the carburetor required in order to use the dashpot of the instant invention therewith. Further, the equivalent of the mounting boss 32 such as a mounting bracket removably attached to the carburetor body 14 may be used in lieu of the mounting boss 32.

The dashpot of the instant invention is referred to in general by the reference numeral 36 and includes a housing generally referred to by the reference number 38. The housing 38 includes front and rear halves 40 and 42, respectively, and each of the halves 40 and 42 is generally cylindrical in configuration.

The rear half 42 includes a large diameter portion 44 at its forward end and a small diameter portion 46 at its rear end. The rear end of the small diameter portion 46 is closed by an integral end wall 48 and the end wall 48 is centrally apertured as at 50.

The small diameter portion may be cylindrical in cross-sectional shape although it is preferable that it be hexagonal as illustrated. The small diameter end portion 46 may therefore be engaged by a wrench in order to apply torsional forces on the housing 38 so as to rotate the housing 38 about its longitudinal axis. However, if the small diameter portion 46 is cylindrical in configuration, the aperture 50 may be in the form of a slot so as to receive the blade end of a screw driver for applying torsional forces on the housing 38 or the aperture 58 may be of noncircular configuration so as to receive a tool end of similar cross-sectional shape.

The front or forward half 40 of the housing 38 includes a large diameter rear end portion 52 and a small diameter forward end portion 54. The forward end of the large diameter portion 44 of the rear half 42 includes a radially outwardly projecting circumferential flange 56 which is snugly receivable within the large diameter end portion 52 and the front half 40 of the housing 38 includes an annular forward end wall 58 which is apertured as at 60 and which merges into an integral forwardly projecting tubular neck 62 flared at its forward end as at 64.

The rear end portion of a sleeve 66 is secured within the forward end portion of the tubular neck 62 by means of welding 68 or other suitable means and the forward end of the sleeve 66 is externally threaded as at 70 for threaded engagement in the bore 34 of the mounting boss 32.

An elongated rod 72 is freely slidable through the sleeve 66 and includes a diametrically enlarged head 74 on its forward end whose forward face 76 is slightly radiused. The rear end of the rod 72 projects outwardly of the rear end of the sleeve 60 and includes a considerably larger diametrically enlarged head 78 disposed rearward of the forward end wall 58. The head 78 is of considerably larger diameter than the inside diameter of the tubular neck 62 and accordingly, the head 78 is prevented from forward withdrawal through the tubular neck 62.

A forward cup 80 of resilient rubber, Neoprene or other suitable resilient oil resistant material is disposed within the front half 40 of the housing 38. The cup 80 opens rearwardly and includes a forward end wall which is thickened as at 82.

Further, the open rear end of the cup 80 includes a radially outwardly projecting and circumferential flange 84 and the outer periphery of the flange 84 includes a circumferentially extending and axially projecting rib 86 which projects rearwardly from the rear face of the flange 84.

The cup 80 includes side wall portions which taper slightly forwardly and a partition referred to in general by the reference number 88 is snugly disposed within the large diameter portion 52 and includes a circumferentially extending and axially opening contoured portion including a forwardly opening and circumferentially extending groove 90 in which the flange 84 and rib 86 are snugly received. In addition. the partition 88 includes a forwardly projecting circumferential rib 92 which is snugly telescoped within the rear end of the cup 80.

The partition 88 has a bore 94 formed axially therethrough and the inner surfaces of the rib or projection 92 define a counterbore 96. A circumferential groove 98 is formed in the forwardly facing annular end wall 100 defined at the inner end of the counterbore 96 and a small radial groove 102, see FIG. 5, communicates the groove 98 with the bore 94.

The dashpot 36 further includes a rear cup 104 which may be conveniently made of the same material of which the cup 80 is constructed and the cup 104 opens forwardly and includes a circumferential flange 106 corresponding to flange 84 and a circumferential rib 108 corresponding to rib 86. In addition, the rear face of the annular partition 88 is contoured in a similar manner to receive the flanges 106 and 108 of the rear cup 104 and the rear side of the partition 88 includes a rearwardly projecting circumferential rib 110 which projects axially from the rear face of the partition 88 and is snugly received within the open forward end of the rear cup 104. In addition, the rear face of the partition 88 is contoured as at 112 to form a smooth seat for the inner surfaces of the end wall 114 of the cup 104 when the end wall 114 is displaced forwardly.

A check valve 116 including an annular outer mounting portion 118 and a central circular inner flap portion 120 is seated in the counterbore 96 and a tapered compression spring 122 is disposed between the mounting portion 118 and the forward end wall of the cup 80. Further, the internal space of the dashpot 36 enclosed between the cups and 104 as well as the partition 88 is completely filled with a suitable liquid 124. Further, the rear axial end of the large diameter portion 52 is crimped over the rear surface portions of the outer periphery of the flange 56 as at 126 in order to seal the interior of the area in which the fluid 124 is disposed from the ambient atmosphere.

When assembling the dashpot 36, and assuming that the only parts remaining to be assembled comprise the front and rear cups 80 and 104, the check valve 116, the compression spring 122 and the rear housing 42, the front half or housing 40 is disposed in an upright position in the manner illustrated in FIG. 4 of the drawings. Then, the cup 80 may be inserted in position above the head 78 and substantially filled with the fluid 124. Thereafter, the compression spring 22 and valve 116 may be placed in position. Thereafter, the partition 88 is lowered into position within the large diameter portion 52 and the lower end of the rib 92 will cause some of the liquid 124 disposed within the cup 80 to be displaced upwardly past the valve 116 and into the bore 94 as the partition 88 moves downwardly to its final lowermost position. In addition, any air trapped outside of the projection or rib 92 and inside of the cup 80 will be forced upwardly therefrom between the partition 88 and the cup 80 and expelled between the flange 84 and the confronting portions of the partition 88 as the latter is lowered into final position. Thus, these components of the dashpot 36 may be readily assembled in a manner excluding all air from below the surface of the liquid 124. After these components have been assembled, additional liquid 124 is added to completely fill the partition 88 and then the rear cup 104 is downwardly displaced toward its position illustrated in FIG. 4 with the central portion of the end wall 114 of the cup 104 slightly downwardly displaced so as to expel any air therebeneath outwardly toward to rib or projection and out of the interior of the dashpot 36 between the rib or pro jeetion 110 and the inner surfaces of the walls of the cup 104. Thereafter, the rear half 42 of the housing 38 is placed in position and the upper portions of the large diameter portion 52 are crimped over the flange 56 of the rear half 42 as previously described. By this method of assembly all air or other vapors will be excluded from the interior of the dashpot 36 and will therefore not have adverse affects on the operation of the dashpot.

In operation, the rod 72 may be reciprocated between the first limit position thereof illustrated in FIG. 4 of the drawings and a second limit position with the rear face of the diametrically enlarged head 74 abutting the forward end of the sleeve 66. However, the compression spring 122 yieldingly urges the end wall of the cup 80 forwardly and thus also urges the head 78 and the rod 72 forwardly to a position with the rod 72 positioned as illustrated in FIG. 4 of the drawings. It is to be understood that the throttle linkage 18 is yielding urged (possibly by some spring means not shown) toward the full closed or idle position. However, the spring 122 urges the rod 72 forwardly to its limit position defined by abutting engagement of the forward face of the head 78 with the rear face of the forward or front end wall 58 of the from half 40 of the housing 38. Of course, the spring means (not shown) yieldingly urging the throttle linkage 18 toward the full closed or idle position is stronger than the spring 122 and thus the spring 122 is overridden by the spring means of the throttle linkage 18. However, the operation of the dashpot 36 is such that the flap portion of the valve 116 will fully open so as to allow fluid within the rear cup 104 to pass by the valve 116 and into the front cup 80 during forward movement of the rod 72. The rod 72 may therefore rapidly move to its forward limit position from its rear limit position. However, movement of the rod 72 from the forward position thereof illustrated in FIG. 4 of the drawings to its rearward position with the rear face of the diametrically enlarged head 74 abutted against the forward end face of the sleeve 66 is prevented by the seating of the flap plate 120 on the portion of the end wall 100 disposed inwardly of the groove 98. However, the groove 102 provides restricted communication between the groove 98 and the bore 94 and accordingly, fluid 124 may slowly pass from within the cup 80, into the groove 98 and through the groove 102 during rearward movement of the rod 72. Thus, when the dashpot 36 is supported in the manner illustrated in H68. 1 and 2 of the drawings, the throttle linkage 18 may freely return from a full open position to a position slightly short of a full idle position at which point the throttle linkage portion 20 will abut the radiused end face 76 and be checked in its movement toward the full idle position. As the force of the throttle linkage portion 20 is applied on the forward end of the rod 72 to urge the rod 72 rearwardly, fluid is displaced from within the cup 80 through the metering groove 102 so as to allow the rod 72 to move to its full rear position defining the full idle position of the throttle linkage portion 20.

When the dashpot 36 is supported from the mounting boss 32, a coil spring 130 is disposed about the sleeve 66 between the flared forward end portion of the tubular neck 62 and the mounting boss 32. The spring 130 serves to retain the dashpot 36 in adjusted rotated position relative to the mounting boss 32 and accordingly, the idle speed of the associated combustion engine may be adjusted merely by rotating the entire dashpot 36. Of course, inasmuch as movement of the rod 72 from its full forward position to its full rearward position is maintained constant, adjustment of the full idle position of the throttle linkage portion 20 also automatically adjusts the throttle return cushioning or retarding affect imposed on the throttle linkage portion 20 by the dashpot 36. Further, inasmuch as the dashpot 36 utilizes liquid as the controlling fluid as opposed to a gas, the groove 102 may be considerably larger in etTective cross-sectional area than the size of a comparable groove which would be required if a gas was used as the controlling fluid. Further, inasmuch as a liquid is used and the liquid filled components of the dashpot 36 are fully sealed relative to each other and free of any air, the dashpot 36 is operable through a considerably larger number of operation cycles than would be possible with a dashpot using air contaminated by the ambient atmosphere as the controlling fluid.

if it is desired, the diametrically enlarged head 74 may be omitted and the final idle stop position of the throttle linkage portion 20 may be defined by the forward end face of the sleeve 66, assuming that the rod 72, when in its rearmost position, would have its forward end retracted within the forward end of the sleeve 66. Also, it is to be noted that the fluid 124 may have its viscosity varied so as to specifically adapt the dashpot 36 for use on different carburetors. Thus, it is possible that the only modification, if any, necessary to adapt the dashpct 36 for use in conjunction with one carburetor as opposed to another carburetor may only need to be the utilization of a fluid of different viscosity. Also, it is envisioned that special fluids may be utilized in order that the dashpot 36 may operate in the most advantageous manner in both hot and cold weather.

The foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly all suitable modifications and equivalents may be resorted to, falling within the scope of the invention.

What is claimed as new is as follows:

1. A time delay mechanism comprising a hollow housing including first and second rigid opposite end sections opening toward each other at adjacent ends and being at least substantially closed at their remote ends, a rigid partition including a continuous peripheral portion disposed between the open ends of said end sections having oppositely axially facing outer peripheral side surfaces, said partition dividing the interior of said housing into first and second end compartments within the corresponding end sections, first and second fluid impervious resilient cups disptsed in said first and second compartments on opposite sides of said partition and opening toward the latter, the open ends of said cups including continuous outwardly directed peripheral flanges abutted against the adjacent outer peripheral side surfaces of said partition, the open ends of said housing end sections including continuous radially directed peripheral flanges whose opposing surfaces are abutted against the remote surfaces of the peripheral flanges of said cups, said opposite end sections being secured together against axial separation with said cup peripheral flanges axially compressed between the opposite side surfaces of said outer periphery of said partition and the opposing surfaces of said peripheral flanges on the open ends of said housing end sections forming fluidtight seals between said cup peripheral flanges and said partition and stationarily mounting said partition between said open end peripheral flanges of said housing sections within said cups, said partition defining a fluid flow zone therethrough communicating the first and second closed fluid receiving zones defined in said cups on opposite side of said partition, and fluid flow control valve means operatively associated with said fluid flow zone to allow ready fluid flow through said zone from said first zone to said second zone and to restrictively meter fluid flow through said flow zone from said second zone to said first zone, said zones being filled with fluid, said cups including remote end walls, and means operatively connected between one of said end walls and said partition yieldingly urging said one end wall away from said partition, the last mentioned means comprising a compression spring whose opposite ends oppose said one end wall and the adjacent side of said partition, said control valve means being supported in said housing between said adjacent side of said partition and the opposing end of said compression spring, said fluid flow zone comprising a bore formed through said partition, said adjacent side of said housing having a counterbore formed therein generally coaxial with said bore, the end wall of said counterbore having a circular groove formed therein opening axially outwardly of said counterbore and spaced at least slightly radially outwardly from said bore, said control valve means including a valve structure having an annular mounting ring seated against said end wall of said counterbore outwardly of said groove and a central flap member disposed within said mounting ring and connected thereto by a flexible tongue portion extending generally radially between corresponding inner and outer peripheral portions of said ring and flap member, said flap member being positionable over the portions of said counterbore end wall between said bore and said groove, a small generally radial groove in said partition communicating said circular groove with said bore, and said flap member being smaller in plan dimensions than the inner periphery of said ring with the spacing between said flap member and said ring registered with said circular groove.

2. A time delay mechanism comprising a hollow housing including first and second rigid opposite end sections opening toward each other at adjacent ends and being at least substantially closed at their remote ends, a rigid partition including a continuous peripheral portion disposed between the open ends of said end sections having oppositely axially facing outer peripheral side surfaces, said partition dividing the interior of said housing into first and second end compartments within the corresponding end sections, first and second fluid impervious resilient cups disposed in said first and second compartments on opposite sides of said partition and opening toward the latter, the open ends of said cups including continuous outwardly directed peripheral flanges abutted against the adjacent outer peripheral side surfaces of said partition, the open ends of said housing end sections including continuous radially directed peripheral flanges whose opposing surfaces are abutted against the remote surfaces of the peripheral flanges of said cups, said opposite end sections being secured together against axial separation with said cup peripheral flanges axially compressed between the opposite side surfaces of said outer periphery of said partition and the opposing surfaces of zone therethrough communicating the first and second closed fluid receiving zones defined in said cups on opposite sides of said partition, and fluid flow control valve means operatively associated with said fluid flow zone to allow ready fluid flow through said zone from said first zone to said second zone and to restrictively meter fluid flow through said flow zone from said second zone to said first zone, said zones being filled with fluid, said fluid comprising a liquid, said partition including oppositely axially projecting generally cylindrical ribs disposed immediately inwardly of said outer peripheral side surfaces of said partition and snugly telescoped into the adjacent open end portions of the corresponding cups.

3. A time delay mechanism comprising a hollow housing including opposite ends, a rigid transverse partition sealingly secured within said housing intermediate the opposite ends of said housing and dividing the interior of said housing into first and second end compartments, first and second fluid impervious resilient cups disposed in said first and second compartments on opposite sides of said partition and opening toward the latter, the open ends of said cups including continuous peripheral portions sealed relative to the adjacent portions of said housing and secured against axial shifting in said housing, said partition defining a fluid flow zone therethrough communicating the first and second fluid receiving zone defined in said housing on opposite sides of said partition, fluid flow control valve means operatively associated with said fluid flow zone to allow ready flow of fluid through said zone from said first zone to said second zone and to restrictively meter fluid flow through said flow zone from said second zone to said first zone, said zones being filled with fluid, said cups including remote end walls, means operatively connected between one of said end walls and said partition yieldingly urging said one end wall away from said partition, the last mentioned means comprising a compression spring whose opposite ends oppose said one wall and the adjacent side of said partition, said control valve means being supported in said housing between said adjacent side of said partition and the opposing end of said compression spring, said fluid flow zone comprising a bore formed through said partition, said adjacent side of said housing having a counterbore formed therein generally coaxial with said bore, the end wall of said counterbore having a circular groove formed therein opening axially outwardly of said counterbore and spaced at least slightly radially outwardly from said bore, said control valve means including a valve structure having an annular mounting ring seated against said end wall of said counterbore outwardly of said groove and a central flap member disposed within said mounting ring and connected thereto by a flexible tongue portion extending generally radially between corresponding inner and outer peripheral portions of said ring and flap member, said flap member being positionable over the portions of said counterbore end wall and between said bore and said groove, a small generally radial groove in said partition communicating said circular groove with said bore, and said flap member being smaller in plan dimensions than the inner periphery of said ring with the spacing between said flap member and said ring registered with said circular groove.

4. A readily liquid fillable time delay mechanism including an annular partition having means defining a central liquid flow zone therethrough, first and second resilient cups disposed on opposite sides of the partition opening toward each other and the partition, said cups having radially outwardly directed continuous peripheral flanges on their adjacent open ends abutted against the opposing opposite axial face portions of said partition, liquid flow control valve means operatively associated with said liquid flow zone to allow ready liquid flow through said zone in one direction and to restrictively meter liquid flow through said zone in the other direction, said partition including oppositely axially projecting generally cylindrical ribs disposed immediately inwardly of i said axial face portions of said partition and snugly telescoped into the adjacent open end portions of the corresponding cups, said flanges being sealingly secured against said face portions of said partition with fluid tight seals established between said face portions and flanges, said cups and zone being filled with liquid.

5. The combination of claim 4 wherein said cups include remote end walls, and means operatively connected between one of said end walls and said partition yieldingly urging said one end wall away from said partition.

6. The combination of claim 3 wherein said housing includes elongated tubular guide means opening into said first end compartment outwardly of the end wall of said first cup, an elongated rod reciprocal through said guide means and including a head on-its end disposed in said first compartment opposing the outer surface of the end wall of said first cup, at least the outer end of said tubular guide means being exter nally threaded for threaded support from a support member having a threaded bore formed therein, and the end of said rod remote from said head being extendable and retractable relative to the outer end of said tubular guide means.

7. A time delay mechanism comprising a hollow housing, a stationary partition in said housing dividing the interior thereof into first and second end compartments, first and second cups disposed in said first and second compartments, respectively, and opening toward and sealed relative to said partition adjacent their open ends defining first and second closed fluid receiving zones therein on opposite sides of said partition, said partition defining a fluid flow zone therethrough communicating said first and second zones, and fluid flow control valve means operatively associated with said fluid flow zone operative to allow ready fluid flow through said flow zone from said first zone to said second zone and to restrictively meter fluid flow through said flow zone from said second zone to said first zone, said zones being filled with fluid, said cups including remote end walls, and means operatively connected between one of said end walls and said partition yieldingly urging said one end wall away from said partition, the last mentioned means comprising a compression spring whose opposite ends oppose said one end wall and the adjacent side of said partition, said control valve means being supported in said housing between said adjacent side of said partition and the opposing end of said compression spring, said fluid flow zone comprising a bore formed through said partition, said adjacent side of said housing having a counterbore formed therein generally coaxial with said bore, the end wall of said counterbore having a circular groove formed therein opening axially outwardly of said counterbore and spaced at least slightly radially outwardly from said bore, said control valve means including a valve structure including an annular mounting ring seated against said end wall of said counterbore outwardly of said groove and a central flap member disposed within said mounting ring and connected thereto by a flexible tongue portion extending generally radially between corresponding inner and outer peripheral portions of said ring and flap member, said flap member being positionable over the portions of said counterbore end wall between said bore and said groove, a small generally radial groove in said partition communicating said circular groove with said bore, and said flap member being smaller in plan dimensions than the inner periphery of said ring with the spacing between said flap member and said ring registered with said circular groove.

8. The combination of claim 7 wherein said compression spring bears against the side of said ring remote from said counterbore end wall.

l t i I II 

1. A time delay mechanism comprising a hollow housing including first and second rigid opposite end sections opening toward each other at adjacent ends and being at least substantially closed at their remote ends, a rigid partition including a continuous peripheral portion disposed between the open ends of said end sections having oppositely axially facing outer peripheral side surfaces, said partition dividing the interior of said housing into first and second end compartments within the corresponding end sections, first and second fluid impervious resilient cups disposed in said first and second compartments on opposite sides of said partition and opening toward the latter, the open ends of said cups including continuous outwardly directed peripheral flanges abutted against the adjacent outer peripheral side surfaces of said partition, the open ends of said housing end sections including continuous radially directed peripheral flanges whose opposing surfaces are abutted against the remote surfaces of the peripheral flanges of said cups, said opposite end sections being secured together against axial separation with said cup peripheral flanges axially compressed between the opposite side surfaces of said outer periphery of said partition and the opposing surfaces of said peripheral flanges on the open ends of said housing end sections forming fluidtight seals between said cup peripheral flanges and said partition and stationarily mounting said partition between said open end peripheral flanges of said housing sections within said cups, said partition defining a fluid flow zone therethrough communicating the first and second closed fluid receiving zones defined in said cups on opposite side of said partition, and fluid flow control valve means operatively associated with said fluid flow zone to allow ready fluid flow through said zone from said first zone to said second zone and to restrictively meter fluid flow through said flow zone from said second zone to said fIrst zone, said zones being filled with fluid, said cups including remote end walls, and means operatively connected between one of said end walls and said partition yieldingly urging said one end wall away from said partition, the last mentioned means comprising a compression spring whose opposite ends oppose said one end wall and the adjacent side of said partition, said control valve means being supported in said housing between said adjacent side of said partition and the opposing end of said compression spring, said fluid flow zone comprising a bore formed through said partition, said adjacent side of said housing having a counterbore formed therein generally coaxial with said bore, the end wall of said counterbore having a circular groove formed therein opening axially outwardly of said counterbore and spaced at least slightly radially outwardly from said bore, said control valve means including a valve structure having an annular mounting ring seated against said end wall of said counterbore outwardly of said groove and a central flap member disposed within said mounting ring and connected thereto by a flexible tongue portion extending generally radially between corresponding inner and outer peripheral portions of said ring and flap member, said flap member being positionable over the portions of said counterbore end wall between said bore and said groove, a small generally radial groove in said partition communicating said circular groove with said bore, and said flap member being smaller in plan dimensions than the inner periphery of said ring with the spacing between said flap member and said ring registered with said circular groove.
 2. A time delay mechanism comprising a hollow housing including first and second rigid opposite end sections opening toward each other at adjacent ends and being at least substantially closed at their remote ends, a rigid partition including a continuous peripheral portion disposed between the open ends of said end sections having oppositely axially facing outer peripheral side surfaces, said partition dividing the interior of said housing into first and second end compartments within the corresponding end sections, first and second fluid impervious resilient cups disposed in said first and second compartments on opposite sides of said partition and opening toward the latter, the open ends of said cups including continuous outwardly directed peripheral flanges abutted against the adjacent outer peripheral side surfaces of said partition, the open ends of said housing end sections including continuous radially directed peripheral flanges whose opposing surfaces are abutted against the remote surfaces of the peripheral flanges of said cups, said opposite end sections being secured together against axial separation with said cup peripheral flanges axially compressed between the opposite side surfaces of said outer periphery of said partition and the opposing surfaces of said peripheral flanges on the open ends of said housing end sections forming fluidtight seals between said cup peripheral flanges and said partition and stationarily mounting said partition between said open end peripheral flanges of said housing sections within said cups, said partition defining a fluid flow zone therethrough communicating the first and second closed fluid receiving zones defined in said cups on opposite sides of said partition, and fluid flow control valve means operatively associated with said fluid flow zone to allow ready fluid flow through said zone from said first zone to said second zone and to restrictively meter fluid flow through said flow zone from said second zone to said first zone, said zones being filled with fluid, said fluid comprising a liquid, said partition including oppositely axially projecting generally cylindrical ribs disposed immediately inwardly of said outer peripheral side surfaces of said partition and snugly telescoped into the adjacent open end portions of the corresponding cups.
 3. A time delay mechanism comprising a hollow housing including opposite ends, a rigid transverse partition sealingly secured within said housing intermediate the opposite ends of said housing and dividing the interior of said housing into first and second end compartments, first and second fluid impervious resilient cups disposed in said first and second compartments on opposite sides of said partition and opening toward the latter, the open ends of said cups including continuous peripheral portions sealed relative to the adjacent portions of said housing and secured against axial shifting in said housing, said partition defining a fluid flow zone therethrough communicating the first and second fluid receiving zone defined in said housing on opposite sides of said partition, fluid flow control valve means operatively associated with said fluid flow zone to allow ready flow of fluid through said zone from said first zone to said second zone and to restrictively meter fluid flow through said flow zone from said second zone to said first zone, said zones being filled with fluid, said cups including remote end walls, means operatively connected between one of said end walls and said partition yieldingly urging said one end wall away from said partition, the last mentioned means comprising a compression spring whose opposite ends oppose said one wall and the adjacent side of said partition, said control valve means being supported in said housing between said adjacent side of said partition and the opposing end of said compression spring, said fluid flow zone comprising a bore formed through said partition, said adjacent side of said housing having a counterbore formed therein generally coaxial with said bore, the end wall of said counterbore having a circular groove formed therein opening axially outwardly of said counterbore and spaced at least slightly radially outwardly from said bore, said control valve means including a valve structure having an annular mounting ring seated against said end wall of said counterbore outwardly of said groove and a central flap member disposed within said mounting ring and connected thereto by a flexible tongue portion extending generally radially between corresponding inner and outer peripheral portions of said ring and flap member, said flap member being positionable over the portions of said counterbore end wall and between said bore and said groove, a small generally radial groove in said partition communicating said circular groove with said bore, and said flap member being smaller in plan dimensions than the inner periphery of said ring with the spacing between said flap member and said ring registered with said circular groove.
 4. A readily liquid fillable time delay mechanism including an annular partition having means defining a central liquid flow zone therethrough, first and second resilient cups disposed on opposite sides of the partition opening toward each other and the partition, said cups having radially outwardly directed continuous peripheral flanges on their adjacent open ends abutted against the opposing opposite axial face portions of said partition, liquid flow control valve means operatively associated with said liquid flow zone to allow ready liquid flow through said zone in one direction and to restrictively meter liquid flow through said zone in the other direction, said partition including oppositely axially projecting generally cylindrical ribs disposed immediately inwardly of said axial face portions of said partition and snugly telescoped into the adjacent open end portions of the corresponding cups, said flanges being sealingly secured against said face portions of said partition with fluid tight seals established between said face portions and flanges, said cups and zone being filled with liquid.
 5. The combination of claim 4 wherein said cups include remote end walls, and means operatively connected between one of said end walls and said partition yieldingly urging said one end wall away from said partition.
 6. The combination of claim 3 wherein said housing includes elongated tubular guide means opening into said first end compartment outwardly of the end wall of said first cup, an elongated rod reciprocal through said guide means and including a head on its end disposed in said first compartment opposing the outer surface of the end wall of said first cup, at least the outer end of said tubular guide means being externally threaded for threaded support from a support member having a threaded bore formed therein, and the end of said rod remote from said head being extendable and retractable relative to the outer end of said tubular guide means.
 7. A time delay mechanism comprising a hollow housing, a stationary partition in said housing dividing the interior thereof into first and second end compartments, first and second cups disposed in said first and second compartments, respectively, and opening toward and sealed relative to said partition adjacent their open ends defining first and second closed fluid receiving zones therein on opposite sides of said partition, said partition defining a fluid flow zone therethrough communicating said first and second zones, and fluid flow control valve means operatively associated with said fluid flow zone operative to allow ready fluid flow through said flow zone from said first zone to said second zone and to restrictively meter fluid flow through said flow zone from said second zone to said first zone, said zones being filled with fluid, said cups including remote end walls, and means operatively connected between one of said end walls and said partition yieldingly urging said one end wall away from said partition, the last mentioned means comprising a compression spring whose opposite ends oppose said one end wall and the adjacent side of said partition, said control valve means being supported in said housing between said adjacent side of said partition and the opposing end of said compression spring, said fluid flow zone comprising a bore formed through said partition, said adjacent side of said housing having a counterbore formed therein generally coaxial with said bore, the end wall of said counterbore having a circular groove formed therein opening axially outwardly of said counterbore and spaced at least slightly radially outwardly from said bore, said control valve means including a valve structure including an annular mounting ring seated against said end wall of said counterbore outwardly of said groove and a central flap member disposed within said mounting ring and connected thereto by a flexible tongue portion extending generally radially between corresponding inner and outer peripheral portions of said ring and flap member, said flap member being positionable over the portions of said counterbore end wall between said bore and said groove, a small generally radial groove in said partition communicating said circular groove with said bore, and said flap member being smaller in plan dimensions than the inner periphery of said ring with the spacing between said flap member and said ring registered with said circular groove.
 8. The combination of claim 7 wherein said compression spring bears against the side of said ring remote from said counterbore end wall. 